PERSPECTIVES OF GLUCOSE -6-PHOSPHATE DEFICIENCY-OVERVIEW.pptx

Glucose 6-phosphate dehydrogenase deficiency is a genetic disorder

1. PERSPECTIVES OF GLUCOSE -6-PHOSPHATE DEFICIENCY-OVERVIEW

2. Glucose-6-phosphate dehydrogenase (G6PD) deficiency which is a genetic disorder, it is an X-linked hereditary defect caused by the mutations in the  G6PD  gene. G6PD deficiency is one of the most prevalent human enzymopathies affecting more than 400 million individuals worldwide, and particularly in those undeveloped and the resource-limited countries.

3. The clinical phenotype of G6PD deficiency varies significantly from the asymptomatic to neonatal jaundice, kernicterus, or the acute hemolytic anemia following the ingestion of certain drugs during some infections, and notably through eating the fava beans ( favism ).  

4. INTRODUCTION This variability in the clinical phenotypes has been attributed to diverse mutant types in the  G6PD  gene . Till date, > 180 mutations have been reported and recorded worldwide, and each ethnic population presents a characteristic mutation spectrums . For example, in the Chinese population, at least 21 different mutations have been allied with G6PD deficiency .

5. These mutations cause class II (much severe) or class III (mild) deficiencies, in which anemia is not present in daily life, but the hemolytic attack can occur upon ingestion of certain oxidative medicines or foods . Therefore, screening for the affected individuals is critical for prevention of the disease(Gómez- Manzo et al.,2016a).

6. Biochemical assays based on the G6PD-catalyzed production of nicotinamide adenine dinucleotide phosphate (NADPH) are widely availed for newborn screening(Gómez- Manzoet al.,2016b). Despite the success in identifying male patients, measurement of the G6PD activity appears to be inadequate for the detection of heterozygous females due to the lyonization (inactivation of one X chromosome) . To overcome this limitation, many alternative biomolecular assays have been developed, encompassing denaturing high-performance liquid chromatography (DHPLC) , amplification refractory mutation system (ARMS) , the microarray-based assay and the reverse dot blot assay (RDB) .

7. Although each assay has unique advantages in terms of specificity and the sensitivity, a common shortcoming of these methods is that they often involving multiple steps of the post-PCR manipulations, which increase the technical complexity and the risk of amplicon contamination. The High-resolution melting (HRM) is a good choice to obviate the post-PCR ramification; nevertheless, the performance of the dye-based methods is compromised by an inability to precisely identify the mutations(Flores et al.,2017). The MeltPro G6PD ( Zeesan , Xiamen, China) assay is a precisely qualitative diagnostic assay developed based on multicolor melting curve analysis (MMCA) availing dual- labeled , self-quenched probes . This bioassay was designed to detect the genotypes of 16 mutations in the  G6PD  gene, which covers > 95% of the Chinese  G6PD  mutations. The MeltPro bioassay is a closed-tube format performed on a real-time PCR platform, which is a precise biotechnique from which the mutation information is retrieved based on differences in melting temperature ( Δ T m ) compared to the wild-type. One distinct or unique feature of this bioassay is its ease-of-use due to the omission of complex post-PCR manipulations. Moreover, the exact mutations type can be identified based on the predefined  T m  values and the detection channels( Desforges et al.,1991). In this study, researchers systematically evaluated the analytical and clinical performances of the MeltPro G6PD assay. For the analytical research, the accuracy of mutation detection, the limit of detection, the reproducibility, and the cross-platform biocompatibility were evaluated. For the clinical study, a multicenter validation study was performed availing 763 clinical samples collected from three different hospitals in China. Researchers examined both G6PD enzyme activity results and DNA sequencing results.

8. International Journal of Toxicology and Pharmacological Sciences, Perspectives of Glucose-6-Phosphate Deficiency-Overview, Dr. S. Sreeremya , Vol 3(2),pp-72-79.2025.